Physical and electronic structure and magnetism of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mi>Mn</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi>NiGa</mml:mi></mml:mrow></mml:math>: Experiment and density-functional theory calculations

Liu, G. D.; Dai, Xianying; Yu, Shiyong; Zhu, Zhenbo; Chen, J. L.; Wu, Guangheng; Zhu, Hao; Xiao, John Q.

doi:10.1103/physrevb.74.054435

Cited by 174 publications

(82 citation statements)

References 39 publications

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“…In NieMneGa ternary system, two intermetallic compounds, namely Ni 2 MnGa [1,2] and Mn 2 NiGa [3,4], were reported to present in the bcc phase (b) region that covers over a wide range of compositions at high temperature [5]. These two intermetallic compounds all belong to highly ordered L2 1 Heusler structure, but with different atom occupation and space group, as confirmed by experimental and theoretical studies in previous investigations [3,4].…”

Section: Introductionsupporting

confidence: 67%

A new ternary compound (Ni, Mn)2Ga in Ni–Mn–Ga system

Ma¹,

Yang²,

Zhou³

et al. 2010

Intermetallics

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Section: Introductionsupporting

confidence: 67%

A new ternary compound (Ni, Mn)2Ga in Ni–Mn–Ga system

Ma¹,

Yang²,

Zhou³

et al. 2010

Intermetallics

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“…The desired properties of the materials Mn 3?x Ga can easily be tuned by substitution of elements, i.e., variation of the Mn:Ga ratio. The recently discovered ferrimagnetic shape memory compound Mn 2 NiGa exhibits a record-breaking magnetic-field-induced strain of approximately 21% in its single crystalline form [21,22]. Co 2 -based Heusler compounds often follow the Slater-Pauling rule, which is a signature for their half metallicity.…”

Section: Introductionmentioning

confidence: 99%

Electronic, magnetic, and structural properties of the ferrimagnet Mn2CoSn

et al. 2011

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The magnetic ground state of the Heusler compound Mn2CoSn was predicted to be nearly halfmetallic ferrimagnetic with a high spin polarization by ab initio electronic structure calculations.Mn2CoSn was synthesized, and the magnetic behavior of the compound was studied using SQUID magnetometry and x-ray magnetic circular dichroism. The experimental values were found to be in fair accordance with the theoretical predictions. The electronic structure and the crystal structure of Mn2CoSn were characterized comprehensively using x-ray powder diffraction, 119 Sn Mössbauer spectroscopy, nuclear magnetic resonance, and hard x-ray photoelectron spectroscopy. LBNL Disclaimer

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“…The austenite phase of Mn excess Ni-Mn-In alloys is known to be ferromagnetic whereas the martensite phase is generally believed to be nonmagnetic (either paramagnetic or antiferromagnetic) [6,8,11], whereas in the Mn excess Ni-Mn-Ga alloys, both the austenite and the martensite phases are reported to be ferrimagnetic [10,[16][17][18]. Using high-resolution synchrotron and laboratory x-ray powder-diffraction (XRD) data, it is shown that the martensite structure can be stabilized by residual stresses over a wide temperature range well above A f in both alloy systems.…”

mentioning

confidence: 99%

Residual stress induced stabilization of martensite phase and its effect on the magnetostructural transition in Mn-rich Ni-Mn-In/Ga magnetic shape-memory alloys

et al. 2015

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The irreversibility of the martensite transition in magnetic shape memory alloys (MSMAs) with respect to the external magnetic field is one of the biggest challenges that limits their application as giant caloric materials. This transition is a magnetostructural transition that is accompanied with a steep drop in magnetization (i.e., M) around the martensite start temperature (M s ) due to the lower magnetization of the martensite phase. In this Rapid Communication, we show that M around M s in Mn-rich Ni-Mn-based MSMAs gets suppressed by two orders of magnitude in crushed powders due to the stabilization of the martensite phase at temperatures well above M s and the austenite finish (A f ) temperatures due to residual stresses. Analysis of the intensities and the FWHM of the x-ray powder-diffraction patterns reveals stabilized martensite phase fractions as 97%, 75%, and 90% with corresponding residual microstrains as 5.4%, 5.6%, and 3% in crushed powders of the three different Mn-rich Ni-Mn alloys, namely, Mn 1.8 Ni 1.8 In 0.4 , Mn 1.75 Ni 1.25 Ga, and Mn 1.9 Ni 1.1 Ga, respectively. Even after annealing at 773 K, the residual stress stabilized martensite phase does not fully revert to the equilibrium cubic austenite phase as the magnetostructural transition is only partially restored with a reduced value of M. Our results have a very significant bearing on the application of such alloys as inverse magnetocaloric and barocaloric materials. Recent years have witnessed a tremendous surge in the study of ferroic and multiferroic materials exhibiting giant caloric effects that can be used in solid-state refrigeration at temperatures close to the ambient conditions as an environmentally friendly substitute to conventional vapor compression refrigeration [1][2][3][4][5]. The Heusler-type Mn-rich Ni-Mn-X (X = Ga, In, Sn, or Sb) magnetic shape memory alloys (MSMAs) have emerged as a potential family of alloys that can exhibit giant barocaloric, elastocaloric, and inverse magnetocaloric (i.e., cooling during magnetization and heating during demagnetization in contrast to normal magnetocaloric materials which heat up on magnetization and cool down by its removal) effects [6][7][8][9][10]. The giant inverse magnetocaloric effects (MCEs) and barocaloric effects (BCEs) in these alloys are linked with a first-order martensitic transition, which is a magnetostructural transition involving change in crystal structure as well as huge drop in magnetization ( M) between the austenite and the martensite phases [11]. This transition involves a large isothermal entropy change ( S iso ) and hence a large adiabatic temperature change ( T ad ) that leads to the caloric effect [8,12]. One of the major limitations of these otherwise potentially promising Heusler alloys is the irreversibility of the martensitic transition as a function of magnetic-field cycles due to the sluggish kinetics of the first-order structural phase transition [8,[13][14][15]. As the MSMAs owe their large inverse MCEs and BCEs due to strong coupling of magnetic an...

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Physical and electronic structure and magnetism ofMn2NiGa: Experiment and density-functional theory calculations

Cited by 174 publications

References 39 publications

A new ternary compound (Ni, Mn)2Ga in Ni–Mn–Ga system

A new ternary compound (Ni, Mn)2Ga in Ni–Mn–Ga system

Electronic, magnetic, and structural properties of the ferrimagnet Mn2CoSn

Residual stress induced stabilization of martensite phase and its effect on the magnetostructural transition in Mn-rich Ni-Mn-In/Ga magnetic shape-memory alloys

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